"Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him through baptism into death, so that as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life. For if we have been united with him in a death like his, we shall certainly be united with him in a resurrection like his. "
When we are baptized into Christ, we are baptized into His death, and therefore into His burial and resurrection as well. Through baptism we are united with Christ in His death, burial and resurrection; and being united with Him in this manner we rise to new life, leaving behind our old self and rising to a new. Baptism is when our old self dies and our new life begins. Baptism is when we stop living for ourselves and start living for Christ. Through baptism we die to ourselves and exchange our life for His. Baptism is also when we come into contact with the blood of Christ. It is in baptism that we “die” with Christ…and so we therefore will live with Him as well.
In other words, what happens in baptism is that God takes Christ’s death, burial, and resurrection and transposes it onto our life. Our old, sinful self becomes united with Christ in His crucifixion and death through baptism and we rise from the water to new life. This is how we “obey the gospel” (2 Thessalonians 1:8) and how we “put on Christ” (Galatians 3:26-27).
Faith + Repentance + Baptism = Salvation
Once you have crucified your old ways (sins) and you repent, the dead person must be buried. Baptism, a burial in water, equates with the death, burial, and resurrection of Jesus Christ. This is the Biblical way to be born again to new life.